Firing-gear.



PATBNTED MAY 21, 1907.

PATBNTBD MAY 21, 1907.

' L. v. BBNT & H. A. MBRGIE.

PIRING GEAR. M A PPLIUATION FILED AUG. 20, 1906.

4 SHEETS-SHEET 2.

mkg?

A No. 854,557.

PATENTED MAY 21, 19o?.

L. v. BBNET & H. A. MBRGI.

. FIRING GEAR. APPLICATION I'ILED AUG. 20. 19o-B.

4 SHEETS-SHEET 3.

`UNITED STATES PATENT OFFICE.

LAURENCE V. BENT AND HENRI A; MERCIE, OF PARIS," FRANCE.'

A I Flame-GEAR. i

To all', whom it may concern:

ments in iiringmechanism for automatic guns, and it relates more especially to means for causing the gun to fire continuously yand automatically as long as it is supplied with ammunition, or to cause the gun to fire single shots at the will of the operator.

With automatic guns as now most generally in use, more or less skill on the part of the operator is-'reguired to fire single shots from the gun, and 1t frequently happens that volleys are tired against the wishes of the operator. With the herein described apparatus,` by a simple adjustment, the gun' is caused to iire continuously and automatically, or automatically in single shots, and

is under absolute control of the operator.

' andA returned to the The invention is intended to apply to thoseautomatic guns which are operated by a reci rocating piston or plunger, which is moved) backward by the gases` of discharge initial position by the return spring. AAmong guns of this class are .the wellv knovn Hotchkiss automatic guns,

for instance, as vare illustrated and,

such, described 1n the patents to Bent & Merci, Nos. 588,380,

granted August 17,' 1897;

696,306,5ranted March 25, 1902, and 804,699,

granted November'll, 19.05.

^ In the accompanying. drawings the apparatus is shown as applied to a gun of the Hotchkiss type just referred to, but obviously it will be applicable to anniT gas operated gun having a reciprocating piston with a return spring for positlon. 4 In the accompanying drawings Figure 1 shows a section through the pistol gripsecured to the breech casing of the gun. Parts of the breech casing are omitted for the sake of 'clearness in the drawings and the heell of thcreciprocating'piston is shown in dotted lines. In this figure the piston is shown' as located in the rear'position with the parts in Specification of Letters Patent. Application tiled August 20,1906. Serial No. 331,341.

j ally similar view Y fromthe opposite side of Fig. 8.

restoring the piston to ythe initial y -curved tail piece E2,

' means of the sprinfr F to Patented May 21,1907.

position for lcontinuous automatic iiring when the trigger is pulled. Fig. 2 is a generto Fig. 1, exceptthatthe trigger has just been pulled and the piston is about to be' released. Fig. 3 is a similar view to Figs. l and 2, but showst the cam set' for single shot fire. lIn Fig. 3 the trigger' is only partly drawn backward.' Fig. 4 isA a similar view to ig. 3, but shows the trigger drawn backward still farther, and shows the detentdisengaged from the trigger, and restored to the position for stopping the forward movement of the piston. In Figs.V 3 and 4 the return spring is omitted for the sake of cle'arness in the drawings. Fig'. 5 is a front view of the pistol grip and parts carried thereby, as seen romthev right of Fig. 1. Fig. 6 represents a section along the line 6 6 of Fig. 1, and looking in the direction of the arrows, the cam block being shown in elevation. Fig. 7l represents a section along the broken line .7-7. of Fig. '1, and looking in the direction-of the arrows. Fig. 8 isa side elevation of the pistol grip, and the parts carried thereby, as seen from the left of the gun. Fig. 9 is a detail showing the cam block and the lever for 'operating the same, as seen' detail showing the cam block in plan with the case for the locking pin iii-section. Fig. 1 1 is a perspective viewoi the detenton a larger scale thanis shown in the other figures.

A represents the. reciprocating piston, which is driven rearward by the powder gases, and-moved forward again by thereturn spring C inthe well known way. This piston reci rocates in a casing B, in rear of the bore o other casing D is connected, which, for convenience of reference, we will call the pistol grip casing, this casing D carrying the hollow pistol grip D', the guard D2 for the trigger, and being provided with chambers to receive the 'firing mechanism, hereinaterto be described. V y E represents the trigger block, which carries a downwardly projecting trigger E', and 4a which-has an inclined plane face e', and a tail lpiece e2.' This triggerblock also carries an eye e3, connected by the plate G, which closes the front of tlcie chamber d? in the pistol grip easing. Shoulders d are provided at the bottom of this chamber d3 at either side of theyslo't d2, vthrough which 'the trigger Fig. 10 is a thegun, and to this casing an- IOO los

passes in assembling the parts. The trigger' block E is provided with shoulders el! to rock on these shoulders f7, and thus permitl the trigger block to rock through a small angle about a pivot near its forward end. The trigger block is drawn backward in the casing D when the trigger is pulled, and when the trigger is released, the trigger block is restored to the initial oriorward position by the spring F.

H represents the detent shown in perspcc tive in Fig. 11. This detent has a hook 7i adapted to engage the hook a on the piston, when desired, and to be disengaged therefrom, as will be hereinafter described. This detent is provided with a rounded tace 7i adapted to rock on a shoulder 7) in the breech casing, and is pressed toward this shoulder b v means of' the spring I. The lower end of the detent terminates in a tongue H beneath the shoulders 713, and this tongue terminates in a hook 71?, adapted to engage the hook e on the trigger block. The shoulders 7i are normally h'eld clear of the bottom of the casing b v the spring I which tends to swing the tail end of the trigger block upward, thus lifting the detent slightly.

The detent is perforated, as at 729, to permit the free passage therethrough of the spring C, and the heel H of the detent is provided with a socket 7i* with spiral grooves h5 therein, so .arranged that the spring I can screw into these spiral grooves, and thus the spring can be conveniently assembled with the detent. 4In rear of the hook 71Y the detent is provided with a rounded face 7i. between two guide lugs 717, and in iront of the hook there is an inclined face 71,D between the guide lugs 71S. This arrangement permits the hook a to pass freely between saidguide lugs', but to engage the hook rwhen the latter 1s 1n the operative position. It will be seen that the detent is a heavy piece which extends across the interior of the breech casing and fits loosely therein, thus affording a very substantial stop to the mot-or piston and having no pivot pin is not likely to wear excessively or get out of order from 'continued'usage The free end of the spring I rests in a socket d* in the block D4, which is secured to or inte` gral with the pistol grip casing. The upper wall of this socket d1 is inclined, as atd, for

e convenience of assembling the parts.

K represents a rotary cam block, which is rovided with an arm K, and a thumb lug 7c', whichV thumb lug also constitutes a casing for the locking pin K2 and the spring K3, which normallyT presses said locking pin outward.

-The locking pin is provided with a coned point k2, which maybe snapped into or sprung out of one of the indentations ds or dg in the casing D. This cam block K is provided with a cylindrical portion K, which is cut away, as at ks, to form a sector 7c, and is prof vided with a lug 7c* for holding the cam block -in place. This lug 7c* is passed through the transverse opening r in the side of the casing D,and is then turnedinto the annular recesf. d?, after the manner of a bayonet joint. Thus this caonmblock may be conveniently applied to, or removed from, the gun, when desired, and may be rotated through an angle and held in two different positions b v means of the locking pin 7Ll engaging in either thc recess d8 or the recess d?, see Fig. S.

The cylindrical portion K4 of the cam block is so cut away, as at lti, that when the sector le is turned upto the position indi cated in Figs. 1 and 2, the said sector will not touch the heel E2 of the trigger block at amv time during the travel of said block; but when the sector 7c is turned down to the po sition indicated in Figs. 3 and 4, the said sector will lie in the' path of the inclined plane e and will press the tail of the trigger piece, vthe trigger is drawn to the rear.

Having thus described the construction oi the parts, the o eration is as follows. Sup- )ose that it is t esired to fire automatically. bwing the cam block until the pin K2 engages the recess dg, 'as shown in Fig. 8. cause the cam sector' 7c to assume the position shown in Figs. l and 2, when. it will be out of the way of the trigger block.A Now open the breech, and load the gun, then pull on the trigger and hold it in its backward position, as shown in Fig. 2v. This will cause the hook e to uil the hook 7a2V back, disengaging the hook from the hook a, andallowing the piston to iiy forward under the action of the spring C. The 0un will now be tired, and the powder gases will' drive the piston back ward again, and since the hook 7i will be held out oi engagement with the hook a as long as the trigger is held back, the automatic firing will continue indeinitely, so long as the trigger is held back, provided'the gun be ,supplied with ammunition.y Whenthe trigger is released, the1 trigger block will fly forward., under the'action of the spring F, and the detent will assume the position shown in Fig. 1,

the hook 71, engagingv the hook a on the irst forward strokel of the piston thereafter, and the gun will cease firing until the trigger is pulled again. Of :course if the gunner isteX- pert enoughhe may, by pulling' thc trigger quickly, and at the rightinterval, cause the gun to fire single shots, even thoughit is arranged for. automatic firing, but this requires considerable y experience, and' .single shot. tiring is positively etfecte'd,\and without any Yskill on thepart of `theoperator,by turning the cam sector 7c tothe position shown in Figs. 3 and 4, which is accomplished bysnapping the pin'K2 into the opposite recess (78,. see Fig. 8. It will-be seen that .when the trigger is dra'wn back to theA position shown in Fig. 2, `the spring F will tend to rock the and with it the hook e, downward when ICO - hook h2 will be, released, as

l .abutment b in the breech i Anextshot, theigunner trigger block E upward about the point e, causing the hook e tov continue inv engagement with thehook h2, but when the cam sector is turned down to the position shown inFigs. 3 and 4, aslight 'movement of the trigger block to the rear will cause the inclined face e to strike the cam sector, as shown in Fig. 3, and vfurther movement of the trigger blocK to the rear willrock'the trigger block E downward about point e11 against the 'action of vthe spring F, and' will wedge the hook e out of en'- gagement with the hook 71E. Thus before. the trigger is brought to its rear position, the showninFig. 4, d. by the spring I causing the hook and the detent will be rocke back to theinitia'l position, h to engage the hook a when ,the piston starts forward again after the gun lias been fired. "It will be'noted that the detent H rolls about itsc'urved 'face 71, against the casing.' "Thus it will be yseen that the mere act' of pulling back the trigger will release the piston and will 'allow it to ily forward, thus 'firing the gun;

while before the piston returns. to the back- ,ward position again, the` detent has been .re-

" leased from engagement with the triggerA v-. block, and the hook thas been restored to e engaging position,`with regard to the 'hook a, and consequently vthe piston is kept from returning again to the forward position, 'aftera single shot has been vfired. To fire the lets. e0 the trigger again", and-the trigger block is drawn by the spring F to the initial .position withk the hook- 'ein front of and engaging the 'hook h2, as

shown in Fig. 1, when the cycleV may be repeated. After a single shot has n with the cam sector in the-position? shown in Figs. 3 a d 4and after the trigger has been returned to the initial position, to fire a second-shot thev cartridge must be inserted and thetrigger ulled again', as before,-andthis single shot ing will continuel indefinitely as long as'the cam sector is maintainedin-the position shown in'Figs. 3 and 4.

fired,

the hooks h2 It will benoted that the backs the hooks and e, are so in- L and a, also of V clined kas to permit theorie hook to wedge by n, strikes aroundthe' face .77,9

rss

g tion from the disengaged position; 'llhus the otherv in returning .to the engag' osiwhen thev piston recoils, the back'o the hook of the detentH, and presses thedetent Vdown againstthe liiting action ofthe spring lF'just enough to allow the hook ato pass, .snapped up'again into the engaging position by saidspring Again the hook e eliglages the b vthe trigger blockpE-Pis wedged down slightly, rocking aboutth'fpoint e11 against the action et the book ete pass the hook 7b2, an it'. then swings up into engagement therewith under the ac' tion of the spring F. ,Thus it will be seen' when the detent is when .the back of ack of the hook L,

spring F, yielding enou h to allow the fromgthe exterior of the apparatus, which could be used without deent of the United States,

-means controlled by said oi" a trigger pulled by hand, device is provided operated gun, which permits-- either single shot fire or. automatic iireat the will of the operator.

It will belobvious that various modifications mightbe made in the herein described parting from the spirit of our invention.

aving thus described our invention, what 'we claim and desire to secure by Letters Patis '1. In' an automatic gun, the combination 'with a reciprocating piston for operating the breech mechanism and a main spring for returning the piston to the forward position, of a detent perforated to permit the passage therethroughy of-'said spring adaptedto hold said piston in a rearward position, a trigger, trigger for releasing .said `detent from engagement with said vpiston, and means for autom lsaiddetent to the matically restoring said detent to initial position when said trigger controlled means is thrown o'ut of engagement 'with said detent, substantially as described.'

2. In with a reci rocat' iston for o erati the breech merihanisiiii) a rolling dtent :ilapted to hold said piston'- in a rearward position, a trigger, means controlled by said trigger for releasing said detent, means for automatically throwing said trigger controlled means ail-automatic the combination IOC out oi' engagement' with said detent when said trigger is pulled, and means for autothe initial position when released, substantially as dea trigger, means controlled by tent from' engagement with back to theinitial position 3. In an automatic gun,\ the combination with a reciprocating piston for operatin the breech mechanism of a rolling detent adapted to hold said piston in a rearward position,

for releasing said detent, a cam for throwing said trigger said means out of engagement with said detent if desired when said trigger is pulled, means for throwing said cam into and out of engagement with said trigger controlled means,'and means for automatically restoring said detent to the initial position when released, substantially as described.v y

4. In an' automatic gun, the combination with a reciprocatingfpiston for operating the breech mechanism, oa detent perforated to permit the passagel therethrough of the piston spring and mounted to rockin the breech i casing andA adapted to hold said piston in' a rearward position, a trigger, means controlled by said trigger for releasing said desaid piston, and a spring automaticaily rocking said detent when said trigger nient with said detent, substantially as e- .ically throwing said t out of engagement wit said detent when the same to the initial position throwI "withv a reciprocating scribed.

5. In an automatic gun, the combination with areciplrocating iston for 'operating the breech mec anism, of) a rolling detent mounted to rockin the breech casing and adapted 'to hold said piston in a rearward position, a

trigger, means controlled by saidtrig'ger for releasing said idetent, means for automater controlled means said trigger is pulled, and a spring automatically rocking said detent back to the initial position when released, substantially as described. l

6. In an automatic gun, the combination with a reciprocating iston for operating the breech mechanism, o a rolling detent mounted to rock the breech casingv and adapted to hold sai? piston in a rearward position, a

trigger, means controlled by said trigger for releasing said detent, a cam for throwing said means out of enga ement with said detent, if desired, when sai trigger is pulled, means for throwing said cam into and out of engagement with said trigger controlled means, and a s ring automatically rocking said detent bac to initial positionwhen released, substantially as described.

7. .In an automatic gun, the combination with a reciprocating piston for operating the breech mechanism, and a spring for restoring of a detent perforated to receive said spring loosely fitting the breech casingand adapted to arrest said iston on its forward stroke,rand a trigger b ock adapted to engage sa'd detent and the-same out; of engagement with said piston, substantiallyv as described.I 8. In an automatic gun, the combination liston for operating the breech mechanism, o arolling detentmoujnted in the breech casing and adapted to arrest saidpiston on its forward stroke, a trigger block adapted to. engage said detent and throw the same out of engagement with said iston, means for disengaging said trigger lock from said detent ata predetermined point of the movement of the trigger, and means for automatically restoring the detent to the initial position, ysubstantially as described. v

, 9. In an automatic gun, the combination witha reciprocating piston for operating the breech mechanism, o a rolling detent mounted inthe breech casing and adapted to arrest said piston on its forward stroke, a trigger throw the same out of engagement with said piston, a trigger carried by said tri ger block, meansfor throwing said trigger b ook out of engagement with said detent at a predetermined point of the travel of'said trl ger, with means for automatically restoring t e detent permit the ypassage forward stro e,

engage said 'detent and throw the same out .of engagement with said, piston, a'nd springs'4 block, with with' a reciprocating piston for o erat' ahoo of.

engage said detent' and to ly as described.

with a reciprocating iston for operating the breech mechanism, o

ay detent perforated to tothe initial position 'when released from engagement withf'vsaid' trigger block, substan- Vtia therethrough ofthe pis;

ton spring and; 'loosely iitting the breech cas;

ingand adapted to arrest said .pistonon its forward stroke, a trig er block adapted to engage said detent an of engagement with said vpiston .with means for restor' .said detent and said trigger block to the initial position, when released, sub;

stantially as described.

11. In an automatic gunthe combination with a reciprocating iston'for operating the breech mechanism, o a detent erforated'to permit the passage therethroug ofl the piston spring and loosely fitting the breech casing yand ada ted to arrest said piston on its a trigger block adaptedto for restoring thedetent and trigger block to the initial position, .when released, substan- .tially as described.

12. In an automatic gun, the combination with a reciprocating breechmechanismo arolling detent mounted in the breech casing and adapted to arrest said piston on its forward stroke,V a sliding trigger block adapted to engage said detent and throw the same out of ,engagementwith j said piston,a triggercarried y said trigger means for disengaging said trigger block from said detent at a. predetermined oint of the movement of the trigger, means p or automaticall lrestorin to the'initiaflpositionipihen ,reIeased, Aand means for restoringl the trigger; block to the initialA position when released,'} as described. f l

i3. In an automatic gn', the c'dmbination the breech mechanism, provided wit a spring impressed detent perforatedto permit the passage therethrou h of the spring andmounted toroc in the casing and adapted to engage said hook and' the detent substantially ythrow the same out g iston for operating the roo.

iston reech arrest said piston on its forward stroke, and

a spring constrained trigger block adapted to engage said detent and throw the same out of engagement lwith said piston, when drawn rearward, said detent and trigger block returning to the "initial position under the' yaction of their respectivev sprin s when released, substantially as describe 14. In. an automatic gun,the combination with'a reciprocating piston for o eratin the breech. mechanism, rovided witl-l a hoo o a spring limpressed etent mounted to roll in the breech. casing Aand adapted to engage said hook and arrest said piston' onr itsl forward stroke and a spring constrained trigger at will mined point of the travel of sition under the action of their "block adapted kengage said detent and throw thev same out of engagement with said piston. .when drawn rearward. -sai'd detent and trigger-block returning to the initial posprings when released, with means operable -for` disengaging said trigger block from said detent at a'predetermine point of the movement' ofthe trigger block, substantiall)T as described.

' 15.- ln an automatic gun, the combination with a reciprocating piston 'for operating the breech mechanism, rovided with a hoo of a spring impressed etentmounted to ,roll in the breech casing and adapted to engage4 said hook and arrest said piston on its forward stroke, and a spring constrained trigger block adapted `to engage said detent and throw the same out of engagement with said piston, when drawn rearward, `said detent and trigger block returning tothe initial position-under the action of their respective springs when released, a trigger carried by said trigger block, and means operable atl -will forvthrowing said trigger block out of engagement with said detent at a predetersaid trigger block,"substantially as described.

16. lIn anautomatic gun, the combination Witli a'reciprocating iston for operating the breech'mechani'sm, o a rolling detent mounted in the breechcasing and adapt-ed to arrest said'piston on its forward stroke, a trigger blockadapted to engage' said detent and throw the same out of engagement with said piston', means for restoring said detent and said tri gerl block to the initial position,

when re eased, and means for disengaging said trigger block from said detent at a predetermined pointfof the movement of said trigger block, substantially as described.

1,7. In an automaticgun, the combination with a reciprocating iston for operating the breech mechanism, o 'a rollin'detent mounted in the; breech casing and adapted to arrest -said piston on its forward stroke, aI trigger `lblock adapted: to engage said detentl and throw the same out ofengagement with said piston, springs for-restoringthe detent and -trigger ook to the initial position, when re- .leased,and.means for disengaging said trigger,block from sald detent at a predeter.

' mined point'of Vthe movement of said trigger block,'substantiallwT as described.

A18. `In an automatic gun,`the combination with areciprocating iston for operating the breech mechanism, o a rolling detent mounted in the breech casing and adapted to arrest said pist-on "onits forward strokema sliding trigger blockl adapted to engage said detent i. and throwJthe same out of engagement with ysaid pistoii, `a"trig'ger carried by said trigger 'blockg a movable cam for disengaging said trigger blockLfromsaid detentat a predeter- ".lleedv Point 0f, the movement' of the trigger respective tion when release( substantially as described.

f 19. In an automatic gun, the combination with a reciprocating y :breech mechanisnno a detent perforated to` permit the passage therethrough of the piston spring and loosely fitting the breech casing'and ada ted to arrest said piston on its forward stro ie, Aand a trigger block adapted, when pulled rearward, to engage said detent and throw the same out of engagement with saidpiston, with means for restoring both the trigger block and detent tothe initial position lwhen released, substantiallyas described. l

20. In an automatic gun, the combination with a reciprocating piston vfor operat' fr the breech mechanism provided with a hoo of a rolling detent having a hook `at each end, mounted in the breech casing and having the movement of the trigger, and means for automatically restoring the detent and the trigger block to the initial position, when released, substantiallyv as described.

piston for operating the said detent au a predetermined point,` of the l I ob 21. In an automatic gun, the combination with a reciprocating pistonfor operating the breech mechanism, of a detent perforated to permit the passage therethrough of the pis-V ton spring and loosely iitting t-he breech casing and adapted, to arrest said piston on its forward stroke, asliding trigger block adapted to engage said detent and throwthe sameout of engagement with said piston, a trigger secured to said block, and means for restoring said detent and said trigger block to the initial position, when released, substantially as described. Y

22. In an automatic gun, the combination with a reciprocating piston for operating the breech mechanism, of a detent perforated to permit the passage therethrough of the pist-on spring and loosely fitting the breech casing and adapted to arrest said piston on its for- I2C)v ward stroke,` a sliding trigger block adapted, when pulled rearward, to engage said detent and throw the .same out ofi-engagement with said piston, atrigger secured to said block, and springs for restoring the detent and trigger block to the initial position, when released, substantially as described.

. 23': In an automatic gun, the combination with a reciprocating piston for operating the breech mechanism, of a rolling detent mount' ed in the-breech casing and adapted to arrest said piston on its forward stroke, a sliding trigger block mounted to rock-slightly in said casing and adapted to engage said detent and throw the same out of engagement with said piston, a trigger carried by said trigger block, a cam, means for throwing said cam into the path of said trigger block, when desired., for disengaging said trigger' block irom said detent at a predetermined point` ofthe movement of' the trigger, means for automatically7 restoring the detent to the initial position, when released, and means for restoring the trigger block to the initialposition when released, substantially as described.`

24. In an automatic gun, the combination with a reciprocating piston for operating the breech mechanism, provided with `a hook, of a spring impressed detent mounted torock in the breech casing and adapted to engage said hook and arrest said pistonon its torward stroke, and a spring constrained trigger block provided with a hook adapted toengage said detent and throw` the same out of engagement with said piston, when drawn rearward, said detent and trigger block re-v turning to the initial position under the action of their respective springs when released, saidtrigger block also being provided with an inclined face in rear of said hook, and a movable cam, with means for locking thi` same in or out of position to engage said inclined tace, substantially as described.

25. In an automatic gun, the combination with a reciprocating piston for operating-the breech mechanism, provided with a hook, of a spring impressed detent mounted to rock in the breech casing and adapted to engage said hook and arrest said piston on its torward stroke, and a spring constrained trigger blockadapted to engage said detent and. throw the same out of engagementwith said piston, when drawn rearward, said detent and trigger block returning to the initial position under the action of their respective springs when released, and a movable cam, with means for locking the same in or out of the path of said trigger block, for releasing said trigger block from said detent at a predetermined point of the movement of the trigger block, substantially as described.

26. In an automatic gun, the combination with a reciprocating piston Vfor operating the breech mechanism, provided with a hook, of a spring impressed detent mounted to rock in the breech casing and ,adapted to engage said hook and arrest said piston on its forward stroke, and a spring constrained trigger block adapted to engage said detent and throw the same out of engagement with said piston, when drawn rearward, said detent and trigger block returning to the initial position under the action of their respect-ive springs when released, a trigger carried by said trigger block, a cam, and means operable at will for throwing said cam into engagement with said trigger block and thus throwing the latter out ol engagement with said detent at a predetermined point of ,the travel of said triggerv block, substantially as described.

- 27. In an automatic gun, the combination with a reciprocating piston for operating the breech mechanism, mounted inthe breech casing and adapted to arrest said piston on its trigger' block adapted to engage said detent and throw the same out of engagement with said piston, means for restoring said detent and said trigger block to the initial position,

when released, and a cam arrangement for forward stroke, a.

of a rollingkletent disengaging said triggerV block from 'said (l tent at a predetermined point of .the movement of said trigger block, when desired, substantially as described.

28. In an automatic gun, the combination with av reciprocating piston'for operating the breech mechanism, of a rolling detent mounted in the breech casing and adapted to arrest said piston on its forward stroke, a trigger block adapted to engage said detent and throw the same out of engagement wi th said piston, springs for restoring the detent and trigger block to the initial position, when released, and a cam arran rement for discr'fjaging said trigger block ii'om said detent t a predetermined of said trigger block, when. desired, substantially as described.

29. In an automatic gun, the combination with a reciprocating piston for operating the breech mechanism, a detent mounted in the breech casing and adapted to arrest saidpiston on its forward stroke, a sliding trigger block adapted to engage said detent and throw the same out of engagement with said piston, said trigger block havingan inclined face in rear of said detent, a trigger carried b v said trigger block, a cam arranged in the path of said inclined face for disengaging said trigger blockcfrom said detent at apredetermined point of the movement of the trigger, means for locking said cam in-either the operative or inoperative osition, means for automatically restoring t e detent tothe initial position, when released, and means for restoring the trigger block to the initial position when released, substantially as described.

30. In an automatic gun; the combination with a reciprocating piston for o eratingthe breech mechanism.provided wit 1 a hoo of a rolling detent having a hook at each end, mounted in the breech casing and having the hook at its upper end adapted to arrest said piston on its forward stroke, a trigger block adapted to engage the hook at the point of the movement IOO lower end of said detent and throw the same out of engagement. with 'said piston, acam arrangement operable at 'will for disengagingA determined point of' the movement. of the trigger, and means for automatically restorbreech mechanism,A of a rolling. detent 'mounted in vthe breech casingl and ada ted to arrest said iston von its forward stro e, a'

slidingr .trigger lock mounted to rock slightbT in sa casing and adaptedto engage said detent and throw the same out of e agement with said piston, a trigger carrier by said trigger block, a cam, means for throwing said cam into the path of said trigger block, when desired, for disengagmg sald trlgger block from said detent at a predetermmed pointv of the movement of the trigger, a springvfor automatically restoring the detentto the initial'positin', when released, and a second 'for restoring the trigger block to the spri initia position when released, substantially Vas described.

In testimony whereof, we aix our signa- 25 tures, in presence of two Witnesses.

LAURENCE v. BENT HENRI A. MERCI. Witnesses:'

CHARLES KURER, .'J. A. CHOUINARD. 

